High severity · published Oct 13, 2021
CVE-2021-40476
Windows AppContainer Elevation Of Privilege Vulnerability
7.5
CVSS
2.4%
EPSS
No
On KEV
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H
Attack vector
Local
Complexity
High
Privileges
Low
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)2.4% · higher than 84% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WI
Windows · Microsoft
20h2; 21h1; 1607; 1809; 1909; 2004 · source: NVD
W1
Windows 10 Version 1507 · Microsoft
10.0.0 before 10.0.10240.19086 · source: vendor
W1
Windows 10 Version 1607 · Microsoft
10.0.0 before 10.0.14393.4704 · source: vendor
W1
Windows 10 Version 1809 · Microsoft
10.0.0 before 10.0.17763.2237 · source: vendor
W1
Windows 10 Version 1909 · Microsoft
10.0.0 before 10.0.18363.1854 · source: vendor
W1
Windows 10 Version 2004 · Microsoft
10.0.0 before 10.0.19041.1288 · source: vendor
W1
Windows 10 Version 20H2 · Microsoft
10.0.0 before 10.0.19042.1288 · source: vendor
W1
Windows 10 Version 21H1 · Microsoft
10.0.0 before 10.0.19043.1288 · source: vendor
W1
Windows 11 version 21H2 · Microsoft
10.0.0 before 10.0.22000.258 · source: vendor
W8
Windows 8.1 · Microsoft
6.3.0 before 6.3.9600.20144 · source: vendor, NVD
WS
Windows Server 2012 · Microsoft
6.2.0 before 6.2.9200.23490 · source: vendor, NVD
WS
Windows Server 2012 (Server Core installation) · Microsoft
6.2.0 before 6.2.9200.23490 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-40476
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-40476
Third Party Advisory
http://packetstormsecurity.com/files/164942/Microsoft-Windows-WSAQuerySocketSecurity-AppContainer-Privilege-Escalation.html
Patch
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-40476
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